python3: add traceback.print_exc to help debugging

Signed-off-by: Julien Fortin <julien@cumulusnetworks.com>

ifupdown2/ifupdown/ifupdownmain.py

@@ -351,6 +351,8 @@ class ifupdownMain:
                 # if read_saved_state fails, state file might be corrupt.
                 # Ignore old state and continue
                 self.logger.warning('error reading state (%s)' %str(e))
+                import traceback
+                traceback.print_exc()
         else:
             self.flags.STATEMANAGER_UPDATE = False
         self._delay_admin_state = True if self.config.get(

ifupdown2/ifupdown/main.py

@@ -73,6 +73,8 @@ class Ifupdown2:
             # else:
             if log:
                 log.error('main exception: ' + str(e))
+                import traceback
+                traceback.print_exc()
             else:
                 print(str(e))
                 # if args and not args.debug: